At present, a light-emitting diode is more and more important in a flat panel display technology for having a self-luminosity, a high contrast, a high response speed, a wide view-angle and so on. As a new-generation display apparatus, an organic light-emitting diode (OLED) has a wide development and application prospection in digital products such as displayer. MP3, television, cell phone and in the military field.
The driving mode of the OLED mainly includes an active matrix driving and a passive matrix driving. A drive and control circuit is an indispensable part of an active matrix light-emitting diode, and a performance thereof is directly related to a performance of the entire system. Therefore, a design of a high performance drive and control circuit is very important in designing an active-matrix OLED display. The manufacturing of the active-matrix OLED is complex, and a cost thereof is high, while the manufacturing of the passive-matrix OLED is simple, and a cost thereof is low.
A passive-matrix OLED display panel is shown in FIG. 1 and FIG. 3, which includes, on the base substrate 1, a plurality of bar-like first electrodes 5, a plurality of bar-like second electrodes 3, first signal lines 51 outputting current signals to the first electrodes 5, second signal lines 31 outputting current signals to the second electrodes 3, a light-emitting functional layer 4 arranged between the first electrodes 5 and the second electrodes 3, a passivation layer 2 and separation pillars 6. A principle of driving the OLED display panel is shown in FIG. 1 and FIG. 2. Display units are defined in intersection regions of the first electrodes 5 and the second electrodes 3. The display of the display units are controlled by controlling driving current output to different rows of first electrodes 5 and different columns of second electrodes 3.
As shown in FIG. 1 and FIG. 3, by the passivation layer 2, the first signal lines 51 and the second signal lines 31 below the passivation layer 2 are insulated from the first electrodes 5 or the second electrodes 3 on the passivation layer 2. The first electrodes are formed on the light-emitting functional layer 4, so the first electrodes are generally formed by evaporation, but the first electrode formed by directly evaporating conductive materials is a plane electrode. In order to form a plurality of bar-like first electrodes, separation pillars are formed before evaporating the conductive materials, and then the conductive materials are separated by the separation pillars when evaporating the conductive materials, thereby forming the bar-like first electrodes.
As shown in FIG. 3, in order to separate the first electrode by the separation pillars when evaporating the first electrode, the separation pillar in the related art generally has an inverted trapezoid shape. Included angles formed in the inverted trapezoid are small, so the conductive materials are very easy to be deposited at lateral sides of the separation pillar, and then adjacent first electrodes may be electrically connected accordingly, and thus the display panel may not display normally.